Deliverers of trucks or oversized mobile homes were required by law to obtain a permit before shipping the items into or out of the state.

It also commented that the several statutory exemptions identified above, such as those applicable to border cities and the shipment of livestock, suggested that the law in effect benefited Iowa residents at the expense of interstate traffic.

He analogized the case to Raymond Motor Transportation, Inc. v. Rice, which concerned a similar law in the State of Wisconsin.

[2] In Rice, the Court used a balancing test which compares the nature of the State’s regulatory concern with the extent of the burden to interstate commerce.

Powell reexamined the evidence on the record and determined that the State failed to meet its burden of proof to show that there was any statistically significant difference in safety between the 55-foot and 65-foot trucks.

He worried that the Court’s ruling basically forced Iowa to bow to the policy choices of neighboring states, when the power to make such interstate regulations is vested in Congress by the Constitution.